1. Field of the Invention
The invention concerns apparatus for handling heavy loads, such as a hand-truck or a wheelchair for the handicapped, over a surface with discontinuities such as steps. The invention is equipped with a raising/lowering device on steps that comprises a motor driving the raising/lowering device and during the operation of this device, forces the apparatus to pivot about a horizontal axis.
2. Description of Background
Known apparatus of this kind as a rule will be operated by one person who, when going up or down one or more steps of a staircase, keeps the apparatus in an inclined position, advantageously near the equilibrium position in order to lower the load the person is bearing. The raising/lowering device in the known apparatus is located at the rear of the apparatus' wheels, on the side of the person manoeuvering the chair. When going up a staircase, these means tend to impart a forward pivoting motion to the apparatus, that is, in the downward direction of the staircase. Where a wheelchair for the handicapped is concerned, then the handicapped person when seated in the chair is in danger falling.